New evidence for nearby Solar-like planetary system [Vega]

spaceflightnow.com ^ | 5 Dec 03 | staff

[RightWhale]

New evidence for nearby Solar-like planetary system

PARTICLE PHYSICS AND ASTRONOMY RESEARCH COUNCIL NEWS RELEASE

Posted: December 1, 2003

Astronomers at the Particle Physics and Astronomy Research Councils UK Astronomy Technology Centre (ATC) at the Royal Observatory, Edinburgh have produced compelling new evidence that Vega, one of the brightest stars in the sky, has a planetary system around it which is more like our own Solar System than any other so far discovered.

All of the hundred or so planets that have been discovered around other stars have been very large gaseous (Jupiter-like) planets orbiting close to their star. This is very unlike our own Solar System. New computer modelling techniques have shown that observations of the structure of a faint dust disk around Vega can be best explained by a Neptune-like planet orbiting at a similar distance to Neptune in our own solar system and having similar mass. The wide orbit of the Neptune-like planet means that there is plenty of room inside it for small rocky planets similar to the Earth * the Holy Grail for astronomers wanting to know whether we are alone in the Universe.

SCUBA image with the position of the star (*) and the predicted position and direction of the planet (x) marked. The distance between the star and the planet is equivalent to twice that between the Sun and Neptune. Credit: PPARC

The modelling, which is described today (1 December 2003) in The Astrophysical Journal, is based on observations taken with the world's most sensitive submillimetre camera, SCUBA. The camera, built at the ATC, is operated on the James Clerk Maxwell Telescope in Hawaii. The SCUBA image shows a disk of very cold dust (-180 degrees centigrade) in orbit around the star.

"The irregular shape of the disk is the clue that it is likely to contain planets" explains astronomer Mark Wyatt, the author of the paper. "Although we can't directly observe the planets, they have created clumps in the disk of dust around the star."

The modelling suggests that the Neptune-like planet actually formed much closer to the star than its current position. As it moved out to its current wide orbit over about 56 million years, many comets were swept out with it, causing the dust disk to be clumpy.

"Exactly the same process is thought to have happened in our Solar System", said Wyatt, "Neptune was 'pushed' away from the Sun because of the presence of Jupiter orbiting inside it". So it appears that as well as having a Neptune-like planet, Vega may also have a more massive Jupiter-like planet in a smaller orbit.

The model can be tested in two ways as Wayne Holland, who made the original observations, explains "The model predicts that the clumps in the disk will rotate around the star once every three hundred years. If we take more observations after a gap of a few years we should see the movement of the clumps. Also the model predicts the finer detail of the disk's clumpiness which can be confirmed using the next generation of telescopes and cameras."

Paradoxically the star barely appears in the SCUBA image because it is far too hot to be seen with this kind of detector. Vega is, however, easily seen with the naked eye. It is the third brightest star visible from Northern latitudes and is bluish-white in colour. Tonight you can see it in the west at around 7 pm.

. . .

[RightWhale]

More of the chimera--the search for life. NASA ought to be emulating Lewis & Clark rather than Ponce de Leon. Vega is approaching earth. Approaching the sun.

[OXENinFLA]

Vega?

[mitchbert]

Wega

[My2Cents]

Do Vegans not eat meat?

[KarlInOhio]

Vega!

[RightWhale]

Vega is usually the first star visible in the fall in Fairbanks when it finally starts getting dark again. Big, bright, blue, nearby as far as stars go. If it has earthsize planets it would be an early goal for interstellar travellers.

[RightWhale]

That's funny. Puts a new twist on those who claim to be vegans.

[martin_fierro]

Let's Contact them and find out. <|:)~

[Dog]

Vega was mentioned in the movie Contact.

[Mr. Mojo]

A yes, Vega. ....1/3 of the "summer triangle" (which includes Altair and Deneb), one of the first constellations I remember learning. One of the brighter stars (in apparent brightness). It would be amazing if it had rocky planets between it and its gaseous giant planets.

[Frank_Discussion]

Hot D*mn! My first thought! HAIL TO VEGA!

[VadeRetro]

Owned one (hatchback, not the pictured wagon). Let's hope the star outlasts the car.

[Tree of Liberty]

Vega

[Frank_Discussion]

Something about this makes me very happy. Maybe it's because it is such a close neighbor.

[Question_Assumptions]

From the information I found, it looks like Vega is an A0V (or main-sequence blue-white star) that's throwing off a lot harder radiation than our sun does. Doesn't look like a good candidate for life to me.

[RightWhale]

Considering that Alpha Centauri is a double star and probably wouldn't be hospitable to us, and it's about the closest, Vega as a possibility is very welcome.

[RightWhale]

Right, it's hot. Wouldn't do to be too close to it. Wonder how their ozone layer is holding up?

[JenB]

According to Have Spacesuit Will Travel, which I read when I was 10, Vega does indeed throw off too many bad rays for us. The Vegans were naturally hardened to their effect. But of course, most people these days don't read good SF so...

[hc87]

There isn't anyone to phone there, unless Carl Sagan's Contact aliens are passing through the neighborhood. Vega is only 350 million years old, so there is virtually no chance of multi-cellular life. Plus at three times the size of the sun, Vega will go nova within a billion years.


http://outreach.jach.hawaii.edu/pressroom/1998_vega/

http://www.astro.uiuc.edu/~kaler/sow/vega.html

[Frank_Discussion]

Imagine something akin to the Jovian satellite system here. Maybe it's hot in the inner rocky band of planets, but hospitable moons in the outer ring of gas giants might thrive on a hot star. Life doesn't have to arise only on a planet, consider that.